FUNCTIONAL ELEMENTS IN ALPHA CRYSTALLIN CHAPERONE

描述：白内障是世界上致盲的主要原因。 然而 白内障形成的病因学知之甚少。 最近，能力 α-晶状体蛋白是透镜蛋白的主要成分， 其他蛋白质的聚集和沉淀（分子伴侣样活性） 已经被证明了。 此外，已经表明α-晶状体蛋白 从高分子量的透镜和水不溶性的 级分具有较低的分子伴侣样活性。 根据这些 观察到，已经假设， α-晶状体蛋白对于保持透镜的透明度至关重要， α-晶状体蛋白伴侣样功能的失效导致非特异性 受损的透镜蛋白聚集和白内障的发展。 更好地 了解α-晶状体蛋白的分子伴侣样活性，PI建议 测定α-晶状体蛋白结合位点的氨基酸序列， 使用模型蛋白和新型交联剂的分子伴侣样功能。 本研究中使用的模型蛋白是酵母醇脱氢酶， BB 2-晶体蛋白和γ 2-晶体蛋白。 此外，还将进行实验， 确定各种蛋白质中是否有共同的特征， 在分子伴侣作用期间与α-晶状体蛋白相互作用。 其他具体目标 该建议包括：a）确定 α-晶状体蛋白中的疏水位点已经涉及 分子伴侣样活性和蛋白质聚集，B）研究以确定 疏水位点也是a-晶状体蛋白中的伴侣位点，和c） α-晶状体蛋白的分子伴侣活性及疏水位点的研究 存在于透镜水不溶性部分中。

DESCRIPTION: Cataract is a major cause of blindness in the world. Yet the etiology of cataract formation is poorly understood. Recently the ability of a-crystallin, the major component of lens proteins to suppress the aggregation and precipitation of other proteins (chaperone-like activity) has been demonstrated. furthermore, it has been shown that a-crystallin isolated from lens high molecular weight as well as from water-insoluble fraction has lower chaperone-like activity. On the basis of those observations it has been hypothesized that the chaperone-like activity of a-crystallin is crucial for the maintenance of lens transparency and that failure of a-crystallin chaperone-like function results in non-specific aggregation of damaged lens proteins and development of cataract. To better understand the chaperone-like activity of a-crystallin the PI proposes to determine the amino acid sequences in a-crystallin binding site during chaperone-like function using model proteins and novel crosslinking agents. The model proteins to be used in this study are yeast alcohol dehydrogenase, BB2-crystallin and y2-crystallin. Additionally experiments will be done to determine whether there are common features in various proteins that interact with a-crystallin during chaperone action. Other specific aims of this proposal include a) the determination of the number and make up of the hydrophobic sites in a-crystallin that have been implicated in chaperone-like activity and protein aggregation, b) investigation to see if the hydrophobic sites are also the chaperone sites in a-crystallin and c) studies on of chaperone-like activity and hydrophobic sites of a-crystallin present in lens water-insoluble fraction.